Investigative reporter and Fox News contributor Sara Carter detailed the harrowing journey of an unaccompanied 9-year-old Guatemalan boy who crossed the U.S.-Mexico border on Wednesday night to locate his estranged mother.

Carter encountered the young boy late Wednesday when she noticed him walking alone without any adult guardians. The boy told Carter he had not seen his mother since she left home when he was 2 years old and he had been residing with his grandparents since. 

In heart-tugging footage that aired exclusively on "Hannity" on Wednesday, the boy asks Carter to borrow her cell phone before dialing a number he had for his mother. An emotional exchange can be heard as the child reveals to her that he has safely reached the United States. 

"I'm here," he says. 

SARA CARTER INTERVIEWS SUSPECTED HUMAN SMUGGLER

"It was very emotional for me," Carter told Hannity. " He was trying to talk to me. He was trying to tell his story. He was very nervous. I'm a mother. I know what it feels like when your children are hurting or when any child is hurting. You just want to be able to comfort them and he wanted to speak with his mother. He did speak with his mom, before making this journey."

Relatives of the young boy appear to have hired professional smugglers to help him cross the border, Carter said.

"But this is the bigger picture, right? We have children coming across our border and he is really only one of 20,000 children that are now in our custody. Probably more than 20,000 in over 200 shelters across the United States. And when you talk to people about this and you talk to Border Patrol agents National Guardsmen, people that are working on the front lines … they will tell you that this is the worst part of Biden's policies," she explained.

Carter said President Joe Biden's open border policy has provided a sense of "false hope to so many people and so many children [who] have lost their way."

"Last night, after the show, we went back out on the river… But roads were filled with people. You can see across the river, just you could hear them in the darkness. Making their way with the smugglers down along the river. And then the smugglers loading people up into rafts bringing them across the river with no indication of fear or worry that they were going to be arrested," she said.

"Who is waiting on the other side of the river? Our National Guardsmen who were there all night and they kept saying, they are coming. Boat after boat after boat. And we were watching young people get off. Pregnant women. Families. This is a very serious crisis."

Carter charged the Biden administration with directly "endangering the lives of these children."

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"Because remember," she reiterated, "this young boy is one of the lucky ones. He actually made it. What about all the children that we never see, that we never hear about, the children that don't make [it through] this journey?"

More than 20,000 children and teenagers are currently under U.S. custody, including nearly 17,000 in shelters run by the health department, according to the New York Times. The influx of unaccompanied minors making their way into the U.S.  is expected to only increase in the coming weeks, prompting desperate calls from border patrol agents for the White House to finally address the mounting crisis.